Morus, a
genus of flowering plants in the family
Moraceae, consists of diverse species of
deciduous trees commonly known as mulberries, growing wild and under cultivation in many
temperate world regions.[1][2][3] Generally, the genus has 64 subordinate taxa,[4] three of which are well-known and are ostensibly named for the fruit color of the best-known cultivar: white, red, and black mulberry (Morus alba, M. rubra, and M. nigra, respectively), with numerous
cultivars and some taxa currently unchecked and awaiting taxonomic scrutiny.[5][4]M. alba is native to
South Asia, but is widely distributed across
Europe,
Southern Africa,
South America, and
North America.[2]M. alba is also the species most preferred by the
silkworm, and is regarded as an
invasive species in
Brazil and the
United States.[2]
The closely related genus Broussonetia is also commonly known as mulberry, notably the
paper mulberry (Broussonetia papyrifera).[6]
Despite their similar appearance, mulberries are not closely related to
raspberries or
blackberries. All three species belong to the
Rosales order. But while the mulberry is a tree belonging to the
Moraceae family (also including the
fig,
jackfruit, and other fruits), raspberries and blackberries are
brambles and belong to the
Rosaceae family (also including the
apple,
peach, and other fruits).
Description
Mulberries are fast-growing when young, and can grow to 24 metres (79 feet) tall.[2][5] The
leaves are alternately arranged, simple, and often lobed and serrated on the margin. Lobes are more common on juvenile shoots than on mature trees.[2][5] The trees can be
monoecious or
dioecious.[5]
The mulberry fruit is a
multiple, about 2–3 centimetres (3⁄4–1+1⁄4 inches) long.[2][5] Immature fruits are white, green, or pale yellow.[5] The fruit turns from pink to red while ripening, then dark purple or black, and has a sweet flavor when fully ripe.[2][5]
The taxonomy of Morus is complex and disputed.
Fossils of Morus appear in the
Pliocene record of the
Netherlands.[7] Over 150 species names have been published, and although differing sources may cite different selections of accepted names, less than 20 are accepted by the vast majority of botanical authorities. Morus classification is even further complicated by widespread
hybridisation, wherein the hybrids are fertile.[citation needed]
Black, red, and white mulberries are widespread in
Southern Europe, the
Middle East,
northern Africa, and the
Indian subcontinent, where the tree and the fruit have names under regional
dialects. Black mulberry was imported to Britain in the 17th century in the hope that it would be useful in the cultivation of silkworms. It was much used in
folk medicine, especially in the treatment of
ringworm. Mulberries are also widespread in
Greece, particularly in the
Peloponnese, which in the
Middle Ages was known as
Morea, deriving from the Greek word for the tree (μουριά, mouria).
Cultivation
Mulberries can be grown from seed, and this is often advised, as seedling-grown trees are generally of better shape and health. Mulberry trees grown from seed can take up to ten years to bear fruit. Mulberries are most often planted from large cuttings, which root readily. The mulberry plants allowed to grow tall have a
crown height of 1.5 to 1.8 m (5 to 6 ft) from ground level and a stem girth of 10–13 cm (4–5 in). They are specially raised with the help of well-grown
saplings 8–10 months old of any of the varieties recommended for rainfed areas like S-13 (for red loamy soil) or S-34 (black cotton soil), which are tolerant to drought or soil-moisture stress conditions. Usually, the plantation is raised and in block formation with a spacing of 1.8 by 1.8 m (6 by 6 ft), or 2.4 by 2.4 m (8 by 8 ft), as plant-to-plant and row-to-row distances. The plants are usually pruned once a year during the
monsoon season to a height of 1.5–1.8 m (5–6 ft) and allowed to grow with a maximum of 8–10 shoots at the crown. The leaves are harvested three or four times a year by a leaf-picking method under rain-fed or semiarid conditions, depending on the monsoon. The tree branches pruned during the fall season (after the leaves have fallen) are cut and used to make durable baskets supporting agriculture and
animal husbandry.
Some North American cities have banned the planting of mulberries because of the large amounts of pollen they produce, posing a potential health hazard for some
pollen allergy sufferers.[10] Actually, only the male mulberry trees produce pollen; this lightweight pollen can be inhaled deeply into the lungs, sometimes triggering
asthma.[11][12] Conversely, female mulberry trees produce all-female flowers, which draw pollen and dust from the air. Because of this pollen-absorbing feature, all-female mulberry trees have an
OPALS allergy scale rating of just 1 (lowest level of allergy potential), and some consider it "allergy-free".[11]
Mulberry tree
scion wood can easily be
grafted onto other mulberry trees during the winter, when the tree is dormant. One common scenario is converting a problematic male mulberry tree to an allergy-free female tree, by grafting all-female mulberry tree scions to a male mulberry that has been pruned back to the trunk.[13] However, any new growth from below the graft(s) must be removed, as they would be from the original male mulberry tree.[14]
Toxicity
All parts of the plant besides the ripe fruit contain a toxic milky sap.[15] Eating too many berries may have a
laxative effect. Additionally, unripe green fruit may cause nausea, cramps, and a
hallucinogenic effect.[16]
Raw mulberries are 88% water, 10%
carbohydrates, 1%
protein, and less than 1%
fat. In a 100-gram (3.5-ounce) reference amount, raw mulberries provide 43 calories, 44% of the
Daily Value (DV) for
vitamin C, and 14% of the DV for
iron; other
micronutrients are insignificant in quantity.
Culinary
As the fruit matures, mulberries change in texture and color, becoming succulent, plump, and juicy, resembling a
blackberry.[5] The color of the fruit does not distinguish the mulberry species, as mulberries may be white, lavender or black in color. White mulberry fruits are typically sweet, but not tart, while red mulberries are usually deep red, sweet, and juicy. Black mulberries are large and juicy, with balanced sweetness and tartness.[5]
The fruit of the East Asian white mulberry – a species extensively naturalized in urban regions of eastern North America – has a different flavor, sometimes characterized as refreshing and a little tart, with a bit of gumminess to it and a hint of vanilla.[19] In North America, the white mulberry is considered an invasive exotic and has taken over extensive tracts from native plant species, including the red mulberry.[2][20]
Mulberries are used in pies, tarts, wines,
cordials, and
herbal teas.[2][5] The fruit of the black mulberry (native to southwest Asia) and the red mulberry (native to eastern North America) have distinct flavors likened to 'fireworks in the mouth'.[19]Jams and
sherbets are often made from the fruit in the
Old World.
The tender twigs are semisweet and can be eaten raw or cooked.[21]
The Ancient Greeks and Romans cultivated the mulberry for silkworms; at least as early as 220 AD, Emperor
Elagabalus wore a silk robe.[27] English clergy wore silk vestments from about 1500 onwards.[27] Mulberry and the silk industry played a role in
colonial Virginia.[27]
Pigment
Mulberry fruit color derives from
anthocyanins,[3] which have unknown effects in humans.[28] Anthocyanins are responsible for the attractive colors of fresh plant foods, including orange, red, purple, black, and blue.[28] These colors are water-soluble and easily extractable, yielding natural
food colorants.[2] Due to a growing demand for natural food colorants, they have numerous applications in the food industry.[3][28]
A cheap and industrially feasible method has been developed to extract anthocyanins from mulberry fruit that could be used as a fabric dye or food colorant of high
color value (above 100).[2] Scientists found that, of 31 Chinese mulberry cultivars tested, the total anthocyanin yield varied from 148 to 2725 mg/L of fruit juice.[29] Sugars, acids, and vitamins of the fruit remained intact in the residual juice after removal of the anthocyanins, indicating that the juice may be used for other food products.[29][2]
exploration and collection of fruit yielding mulberry species
their characterization, cataloging, and evaluation for anthocyanin content by using traditional, as well as modern, means and
biotechnology tools
developing an information system about these cultivars and varieties
training and global coordination of genetic stocks
evolving suitable breeding strategies to improve the anthocyanin content in potential breeds by collaboration with various research stations in the field of sericulture, plant genetics, and breeding, biotechnology and
pharmacology
Paper
During the Angkorian age of the
Khmer Empire of
Southeast Asia, monks at Buddhist temples made paper from the bark of mulberry trees. The paper was used to make books, known as kraing.[31]
Tengujo is the thinnest paper in the world. It is produced in Japan and made with kozo (stems of mulberry trees).[32]
Wood
The wood of mulberry trees is used for
barrel aging of
Țuică, a traditional Romanian plum brandy.
Culture
A
Babylonianetiological myth, which
Ovid incorporated in his Metamorphoses, attributes the reddish-purple color of the mulberry fruits to the tragic deaths of the lovers
Pyramus and Thisbe. Meeting under a mulberry tree (probably the native Morus nigra),[33] Thisbe commits suicide by sword after Pyramus does the same, he having believed, on finding her bloodstained cloak, that she was killed by a lion. Their splashed blood stained the previously white fruit, and the gods forever changed the mulberry's colour to honour their forbidden love.[33]
Vincent van Gogh featured the mulberry tree in some of his paintings, notably Mulberry Tree (Mûrier, 1889, now in
Pasadena's
Norton Simon Museum). He painted it after a stay at an asylum, and he considered it a technical success.[34]
References
^J.M. Suttie (2002).
"Morus alba L." United Nations, Food and Agriculture Organization. Retrieved 8 March 2020.
^Ogren, Thomas Leo (2003). Safe Sex in the Garden: and Other Propositions for an Allergy-Free World. Berkeley, California: Ten Speed Press. pp. 22–23.
ISBN1580083145.
^National Academies of Sciences, Engineering, and Medicine; Health and Medicine Division; Food and Nutrition Board; Committee to Review the Dietary Reference Intakes for Sodium and Potassium (2019). Oria, Maria; Harrison, Meghan; Stallings, Virginia A. (eds.).
Dietary Reference Intakes for Sodium and Potassium. The National Academies Collection: Reports funded by National Institutes of Health. Washington (DC): National Academies Press (US).
ISBN978-0-309-48834-1.
PMID30844154.{{
cite book}}: CS1 maint: multiple names: authors list (
link)
^Boning, Charles R. (2006). Florida's Best Fruiting Plants: Native and Exotic Trees, Shrubs, and Vines. Sarasota, Florida: Pineapple Press, Inc. p. 153.
^
abReich, Lee (2008).
"Morus spp. mulberry". In Janick, Jules; Paull, Robert E. (eds.). The Encyclopedia of Fruit and Nuts. CABI. pp. 504–507.
ISBN9780851996387.
^Gogh, Vincent van (1889).
"Mulberry Tree". van Gogh Collection. Norton Simon Museum, Pasadena, California. Retrieved 20 October 2012.